1. Field of the Invention
The present invention relates to a method for compensating data, a data compensating apparatus for performing the method, and a display apparatus having the data compensating apparatus.
2. Description of the Related Art
Generally, a liquid crystal display (“LCD”) apparatus includes an array substrate, an opposite substrate facing the array substrate, and liquid crystal material having an anisotropic refractive index interposed between the array substrate and the opposite substrate. The LCD apparatus displays an image by controlling a strength of an electric field applied to the liquid crystal material to control an amount of light transmitted through the liquid crystal material.
The LCD apparatus typically uses dynamic capacitance compensation (“DCC”) for improving a response time of the liquid crystal material. DCC compensates a present frame data signal using a previous frame data signal to improve the response time of liquid crystal. For example, when a gray scale of the present frame data signal is much larger than a gray scale of the previous frame data signal, DCC overshoots the gray scale of the present frame data signal, e.g., outputs a higher gray scale than the gray scale of the present frame data signal, to improve a rising response time of the liquid crystal material. In contrast, when the gray scale of the present frame data signal is much lower than the gray scale of the previous frame data signal, DCC overshoots the gray scale of the present frame data signal to a lower gray scale than the gray scale of the present frame data signal, to improve a falling response time of the liquid crystal material.
FIG. 1 is a graph of display signals versus time (in frames) showing response characteristics of liquid crystal implementing DCC of the prior art. FIG. 2 is a diagram illustrating rising bounce characteristics of the liquid crystal implementing DCC of the prior art.
Referring to FIG. 1, which is a graph illustrating results of measuring the response characteristics of the liquid crystal when a zero gray scale data signal 0G is received for a previous frame F(n−1) and a 224 gray scale data signal 224G is received for a present frame F(n), based on an 8-bit data signal for a 46-inch display panel (120 Hz driving) with DCC technology. The DCC is applied to the 224 gray scale data signal 224G of the present frame F(n), and the 224 gray scale data signal 224G is compensated to a DCC level, which is higher than a level of the input data, as shown in FIG. 1. Accordingly, when the DCC level is applied to the present frame F(n), a luminance level in subsequent frames drops based on the response characteristics of the liquid crystal, as shown by the rising bounce from an (n+1)-th frame F(n+1) to an (n+6)-th frame F(n+6). Thus, it can be seen that a time required for the luminance level to recover, e.g., to reach the input data level of the data signal, is about seven to eight frames.
Referring to FIG. 2, the rising bounce shown in FIG. 1 substantially degrades a display quality, as shown by a visible blurring behind an edge of a scrolling box pattern BP.